Protective system for airport runway and taxiway light fixtures

ABSTRACT

A system for the protection of airport runway light fixtures and markers is disposed at or near the edge of aircraft runways, taxiway and airport signs. The system includes a thin flexible mat having an axial opening proportioned to enable placement above an elevated in-ground concrete base of a runway light fixture, and peripherally disposed apertures within the mat. The system further includes several anchors for the mat, each of which comprise a planar head, and means for penetration and engagement of earth upon which the mat is positioned. The penetration and engagement elements of each anchor integrally and rigidly depend from a lower surface of the planar head at a central axis. A greatest transverse cross-section of the engagement element is proportioned for complemental insertion within the peripheral apertures of the convex mat. The planar heads of the anchors each engage the mat when the engagement means have fully penetrated the earth upon which the mat is to be secured. The upper surface of the planar head of each anchor preferably includes an axially disposed nut, Allen head screw or the like proportioned for complemental engagement with the drive element of a power tool to effect rotation of the anchor into the earth.

REFERENCE TO RELATED APPLICATION

[0001] This case is a continuation-in-part of application Ser. No. 10/029,923, filed Dec. 31, 2001, entitled Protective System for Airport Runway Light Fixtures.

BACKGROUND OF THE INVENTION

[0002] Present day airports, of whatever size, make use of numerous, often hundreds, of light fixtures for purposes of illumination of the edge of the airport runway, taxiway and parking areas to thereby minimize the possibility that an aircraft will inadvertently travel off the edge thereof. Such airport light fixtures involve considerable cost, both by way of initial capital investment, accidental breakage and maintenance in that the state-of-the-art runway light fixture is designed to withstand intense vibration and high wind velocity encountered in take-off and landing operations of jet aircraft, as well as bad weather. Such fixtures must, as well, remain operable over a broad range of environmental factors including heat, humidity, erosion, dust, wind, vegetation and insects. Accordingly, each runway light fixture represents a significant, but risk prone, capital asset of the airport. In order to protect this asset and to ensure maximum functionality, extensive use of mowing and other equipment is made to trim and limit the growth of grass and vegetation thereabout. However, such equipment may itself cause damage to runway lights. In many areas, it is also necessary to employ plant poisons and pesticides to protect runway lights from insects and the ingrowth of vegetation. Accordingly, the maintenance of runway lights entails not only the cost labor associated with continual trimming of vegetation but, as well, the potentially hazardous use of herbicides and pesticides to protect the light from vegetation, insects, and other small animals which might otherwise damage the runway lighting.

[0003] The prior art has addressed the above problem through the suggestion of complicated and expensive light fixtures or light fixture protectors and, inter alia is represented by U.S. Pat. No. 4,104,711 (1978) to Carter, entitled Airport Light Fixture; U.S. Pat. No. 5,122,798 (1992) to Kaolian, entitled Airport Ground Light Arrangement; U.S. Pat. No. 5,669,691 (1997) to Barrow, entitled Airport Runway or Taxiway Light Fixture; and U.S. Pat. No. 5,971,561 (1999) to Fitzwater, entitled Airport Field Light Protector.

[0004] All of the above solutions, while clearly useful in extending the life of airport runway light fixtures, provide no help in the above-described environmental problems associated with extensive groundwork and other maintenance directed to the, vegetation which inevitably will try to envelop runway light fixtures. A recognition of such limitations in the prior art is reflected in Kaolian above which suggests the use of a semi-rigid disk shaped body formed of a weather-resistant material which comprises an integral part of the runway fixture per se. Therein, the disk requires excavation of earth and insertion of gravel under the disk. In other words, in systems such as Kaolian and Fitzwater above, a protective rigid or semi-rigid disk is essentially integrated as a part of the airport ground light unit. In such solutions, the outermost edge or periphery of such disk-like elements are susceptible to uplifting under the effect of jet blast, ambient wind, water, and the activity of insects and small animals even if the disk is positioned below ground level.

[0005] In addition, the structure of Fitzwater entirely enclosed the breakaway coupling of the light fixture, thereby negating its safety functions. That is, the fixture, in the invention as set forth below, if impacted by any part of an aircraft, will instantly break away and lie flat upon the ground. In Fitzwater, this will not occur.

[0006] Accordingly, none of the suggestions in the prior art which might, superficially, appear related to the present invention, are practical in terms of such long-term external effects thereupon. In addition, it is essential that any peripheral disk, skirt, or the like associated with a runway light be as flat as possible to minimize interference with, or damage to, lower blades of landscaping equipment, the use of which would remain necessary with respect to airport maintenance beyond the periphery of any system for the protection of airport runway light fixtures. It is further noted that the use of gravel to suppress foliage about landing strips has given rise to its own problems; for example, jet blast is capable of dislodging and blowing gravel about a taxiway thereby creating a hazard to other aircraft and to personnel in the area.

[0007] It is, thereby, to be appreciated that prior art attempts to suppress the growth of foliage and to control other factors impacting upon airport ground lights have been relatively ineffective and, as well, have proven costly in terms of manpower, maintenance and particularly the replacement of lights and other components of such ground light systems when damage thereto occurs.

[0008] The present invention thereby represents an effective alternative to such art as Kaolian and Fitzwater, referenced above.

[0009] With regard to U.S. Pat. No. 5,436,812 (1995) to Stewart, entitled Airport Marker System, the same teaches a generally conventional airport runway light fixture system including a metallic base plate and a concrete base thereabout of a type which it is an objective of the present system to entirely cover to thereby preclude encroachment of vegetation and insects upon the light fixture system, this is more fully set forth below.

SUMMARY OF THE INVENTION

[0010] The instant invention relates to a system for the protection of airport runway light fixtures having a co-axial, substantially ground level metallic support secured within an elevated in-ground concrete base. The system more particularly comprises a flexible mat including an opening about a central axis thereof, said opening having a radius substantially equal to that of said concrete base from said light fixture, said mat also having a plurality of peripherally located apertures. The system further includes a plurality of anchors for said mat, corresponding in number to the number of said apertures, each of said anchors comprising a planar head and, integral therewith, means for the penetration and engagement of the ground upon which said mat is to be positioned, said penetration means proportioned for complemental insertion through said peripheral apertures of said mat, wherein said heads of said anchors engage said mat when said penetration means are fully penetrated into the earth upon which said mat is to be secured. In a preferred embodiment, the upper surface of said planar head of each anchor comprises an axially disposed nut, Alan Head screw or the like proportioned for complemental engagement with a drive element of a power tool to thereby effect rotation of the anchor into the earth.

[0011] In view of the above, it is an object of the present invention to provide an improved system for the protection of airport runway light fixtures from airfield maintenance equipment, this inclusive of a protective mat therefore and method of efficient securement thereof to the area surrounding such runway and taxiway light fixtures.

[0012] It is another object of the invention to provide an airport ground lighting system having improved means for the suppression of foliage and pests thereabout.

[0013] It is a further object to provide a system of the above type which will reduce mowing presently associated with runway lighting and lighting fixtures.

[0014] It is a further object to provide an airport ground light system protection for reduction of soil erosion in the area about the fixture.

[0015] It is a yet further object of the invention to provide a means for the protection of airport runway light fixtures not susceptible to uplift under the influence of jet or propeller airblast.

[0016] It is still another object to provide an improved system to enhance the visibility of runway ground lights.

[0017] It is a still further object of the invention to provide a system for the protection of airport runway lights which will reduce the cost of labor associated with the use of herbicides and pesticides about said lights and will reduce risks to workers otherwise required to walk onto or near the airfield for such tasks.

[0018] It is a yet further object to provide a system of the above type which is fully compatible with all sizes and weights of lawn maintenance equipment and which will pose no risk to such equipment or to an aircraft that may inadvertently travel over such a system.

[0019] It is a still further object of the invention to provide a system of the above type which will, through the use of conventional portable power tools, can be quickly installed or repositioned.

[0020] It is a further object to provide a system of the above type which is essentially immovable after it has been properly secured about a runway light fixture or airport sign and into the earth.

[0021] The above and yet other objects and advantages of the present invention will become apparent from the hereinafter set forth Brief Description of the Drawings, Detailed Description of the Invention and Claims appended herewith.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022]FIG. 1 is a perspective view of a first embodiment of the invention.

[0023]FIG. 2 is a bottom view of the runway light protector of FIG. 2 prior to the insertion thereinto of anchors.

[0024]FIG. 3 is a vertical, axial, cross-sectional assembly view of the structure of FIG. 1.

[0025]FIG. 4 is a perspective view of a first anchoring element employed with the present system.

[0026]FIG. 5 is a perspective view of a second type of anchoring element that may be used with the instant system.

[0027]FIG. 6 is a radial cross-sectional view taken along Line 6-6 of FIG. 5.

[0028]FIGS. 7 and 8 are top schematic views showing potential travel paths of edges of airport lawn mowing equipment.

[0029]FIG. 9 is a top schematic view of an elliptical embodiment of the invention of FIGS. 1 though 8 showing the travel path of edges of an airport mowing equipment thereupon.

DETAILED DESCRIPTION OF THE INVENTION

[0030] With reference to the perspective view of FIGS. 1-3, the present system is shown as it appears after the same has been fully installed about an airport runway light fixture 10 of the type which is constitutes that most commonly used at airports. Such fixtures depend upwardly from a rigid conduit 12 and a breakaway or frangible coupling 18 through which run electrical wires 13 (see FIG. 3) which connect to electrical cabling 13A which is provided throughout the periphery of an airport runway. It is to be noted that such cabling 13A passes through an above ground rigid concrete base 14 having a periphery 15 which, in a top view (not shown), will typically define a circle. However, periphery 15 of concrete base 14 may, at certain airports, define a square as viewed in a top view. In either embodiment, periphery 15 of concrete base 14 surrounds a periphery 16 of a substantially ground level metallic fixture support 17 which stabilizes said breakaway coupling 18 and conduit 12 of the light fixture 10. At certain airports, said concrete base 14 is embedded within earth 19. It is to be understood that the present invention does not apply to in-pavement runway lights of typically larger airports.

[0031] Where said concrete base 14 is circular, as is typically the case, periphery 15 thereof will generally have a radius of about twice the radius defined by periphery 16 of metallic fixture support 17.

[0032] The inventive system particularly includes a flexible mat 22 (see FIGS. 1 and 2), typically formed of a rubber or elastomeric material, which includes an axial opening 24 which is co-axial with said conduit 12 of the light fixture. Said opening 24 is proportioned to facilitate placement upon light fixture 10 and, more particularly, is provided with a radius which is substantially equal to the radius or least radial dimension (in the event that metallic support 17 is not circular) of metallic support 17. Therefore, as may be more particularly appreciated with reference to the view of FIG. 3, an innermost edge of mat 22 will abut periphery 16 of metallic fixture support 17. It is further noted that to achieve its objectives, as above set forth in the Background of the Invention, mat 22 must have a radius in a range of about 2 to about 2.5 times the radius of periphery 15 of concrete base 14 if base 14 is circular, or if base 14 is square, mat 22 must be at least two times the average radial dimension thereof, relative to light fixture axis defined by conduit 12, in order to function satisfactorily. Accordingly, in the most common form of airport runway light construction, which is shown in FIG. 3, axial opening 24 of mat 22 will have a radius substantially equal to the radius of metallic fixture support 17 and will have an outermost radius, that is, radius at periphery 29 of mat 22 which is in a range of 2 to 2.5 times the radius (or average radial dimension) of concrete block 14, i.e., about 4 to 5 times the radius of metallic fixture support 17. It has been found that such ratios are advantageous in affording appropriate protection to the light fixture, coverage to concrete base 14, and to an annular region 28 between concrete block periphery 15 and mat periphery 29 to thereby preclude the growth of vegetation unduly close to the runway light fixture and to protect the same from the various other risks such as erosion, as are more particularly set forth in the Background of the Invention.

[0033] The above factors, taken in view of a typical radius of said metallic support 17 of about six inches, would dictate that a typical mat would have a radius of about 24 inches (and therefore a diameter of about 48 inches). A minimum radius of mat 22 would be about 30 inches. The thickness of a typical mat is in a range of about 0.5 to about 1.5 inches. This may be a function of the height of concrete base 14 above earth 19. Given that concrete base 14 will extend above the level of the earth, an inner annular portion 26 (see FIG. 3) of the mat will typically be slightly convex relative to said outer annular region 28. Within said region are provided a plurality of apertures 30 which are disposed near the periphery of the mat 22, the purpose thereof being to enable passage through said apertures of a plurality of anchors 32 (see FIG. 4), each of which includes a planar head 34 wherein said penetration means 36 typically comprise a spiral, the purpose of which is to effect the penetration and maximum engagement of ground upon which said mat is to be positioned.

[0034] A second embodiment of the anchor is shown as anchor 132 in FIG. 6, therein a V-shaped element 136 is employed in lieu of said spiral structure 36. However, in each anchor there is provided a sharp tip 37 or 137 respectively to assist in penetration of the earth. It is more particularly noted that in the embodiment of FIG. 4 (also shown in FIG. 1), the upper surface of the planar head 34 is provided with a protruding hex nut 35 or recessed Alan Head element which is proportioned for complemental engagement with a head of a portable power tool to thereby effect rotation of such element and, thusly, of the entire anchor 32 such that anchors may be quickly inserted into the ground with a minimum of difficulty. It has been found that an inexpensive readily available power tool such as a Makita or Black and Decker power drill may be employed to achieve this end. It has also been found that anchors 32 may be easily inserted into earth having a wide range of soil types. However, when the earth is particularly hard or stone-like, as is more common in northern glacial areas, such as Canada, a spike type anchor of the type of anchor 132 may be employed. However, in such case, a sledgehammer must be used to hammer anchors 132 into such rock-like earth.

[0035] It has been determined that the use of an anchor consisting of a large diameter planar head, the case in both anchors 32 and 132, typically having a radius of two to four inches will, when properly installed, secure mat 22 such that it is immovable under any influence including water, weather, jet blast, vegetation growth, or action of insects. It is thereby most difficult for erosion or vegetation to come close enough to the fixture 10 to impair the runway illumination of the fixture.

[0036] Further, as may be noted with reference to FIGS. 7 and 8, edges 42 mowing equipment of a type typically used at airport can safely pass over annular regions 28 (see also FIG. 3) of the mat, this due to its minimal thickness which, as above noted, is in the range of about 0.5 to about 1.5 inches but, preferably, is 0.5 inches, that is, approximately 13 millimeters. In general, the mat is formed of an elastomeric material, preferably a polymeric plastic, such as an EPDM polypropylene terpolymer. The weight of a mat of the above dimensions made of such material would be about 28 pounds, with a density of 0.68 ounces/cu.inch, and tensile strength of about 650 pounds. Accordingly due to the thinness, strength and flexibility of mat 22, the present system will not interfere with the normal operation of airport mowing equipment. By the same token, there need not be a concern that the wheels or landing gear of an aircraft, which happens to pass beyond the edge of runway or taxiway 20, will be interfered with by either mat 22 or the planar heads 34 of the mat anchors 32.

[0037] In an alternate embodiment of the invention, shown in FIG. 9, there may be provided an elliptical mat 122 in lieu of the circular mat 22 above described. Typical dimensions thereof would be about 48 inches by 84 inches with a weight of about 80 pounds. Such an elliptical mat structure may be advantageously employed in a number of applications where, for example, ground surface, visibility, or aesthetic considerations may dictate. For example, extending the length, in even a single axis, of the mat portion of the present system, will enhance ease of mowing and visibility of light fixture 10 from the aircraft runway 20, even if vegetation or foliage at the edge of the runway is not trimmed for a considerable period of time. Also, resistance to erosion of the earth-surrounding lighting fixtures is increased through the use of the elliptical structure of mat 122. Such a structure, as is also noted in FIG. 9, is completely compatible with use with lawn mowing equipment and, in certain respects, is more suitable for such use in that the turning radii associated with mower travel along the edge of mat 122 is much than is the case of the turning radii associated with mower travel along or upon the periphery of circular mat 22. In FIGS. 7 to 9 the path of travel of the edge of the moving equipment is indicated by numbers 42 and 142.

[0038] It is further noted that mat 22 or 122 may be provided with a threaded aperture holes for the accommodation of so-called snow poles 48 (see FIG. 1) which are commonly used at airports in colder climates during much of the year.

[0039] While there has been shown and described the preferred embodiment of the instant invention it is to be appreciated that the invention may be embodied otherwise than is herein specifically shown and described and that, within said embodiment, certain changes may be made in the form and arrangement of the parts without departing from the underlying ideas or principles of this invention as set forth in the Claims appended herewith 

I claim:
 1. A system for the protection of an airport runway light fixture including a metallic support secured within an elevated, above ground level substantially circular concrete base, the system comprising: (a) a flat flexible mat including an axial opening about a central axis thereof, having a radius substantially equal to a radius of said concrete base, said mat also having a plurality of peripherally located apertures; and (b) a plurality of anchors for said mat, corresponding in number to the number of said apertures, each of said anchors comprising a planar head and, integral therewith, means for penetration and engagement of the ground upon which said mat is to be positioned, said penetration means proportioned for complemental insertion through said peripheral apertures of said mat, wherein said heads of said anchors engage said mat when said penetration means have fully penetrated into the earth upon which said mat is to be secured.
 2. The system as recited in claim 1, in which at least one radius of a periphery of said mat defines a dimension of about 2.0 to about 2.5 times a ground level radius or average radial dimension of said concrete base.
 3. The system as recited in claim 1, in which at least one outer radius of said mat defines a dimension of about 4 to about 5 times a radius of said metallic support.
 4. The system as recited in claim 2, in which at least one radius of said mat defines a dimension of about 4 to about 5 times the radius of said metallic support.
 5. The system as recited in claim 2, in which an upper surface of said planar head of said anchor comprises an axially disposed element proportioned for complemental engagement with a drive head of power tool to thereby effect rotation of said anchor into the earth.
 6. The system as recited in claim 5, in which said penetration means of said anchor comprises an elongate spiral having a pointed tip thereof.
 7. The system as recited in claim 1, in which said penetration means comprises a V-shaped element having a pointed distal end.
 8. The system as recited in claim 5, in which said anchor defines a length of about one foot.
 9. The system as recited in claim 2, in which said planar head of said anchor defines a circle having a radius in a range between about two to about four inches.
 10. The system as recited in claim 9, in which said mat defines a circle.
 11. The system as recited in claim 9, in which said mat defines an ellipse.
 12. The system as recited in claim 1, in which said mat includes therein a threaded recess for the accommodation of a snow pole.
 13. The system as recited in claim 2, in which said mat defines a thickness of between about 0.5 and about 1.5 inches.
 14. The system as recited in claim 2, in which said mat is formed of a rubber or elastomeric material.
 15. The system as recited in claim 2, in which said concrete base is circular at ground level.
 16. The system as recited in claim 2, in which said concrete base is square at ground level. 